[Tumble Mustards: The Genus Sisymbrium in the Columbia River Gorge of Oregon and Washington]
Jim Hill Mustard, Tall Tumblemustard, Tumble Mustard, Tall Rocket Mustard
Sisymbrium altissimum
Synonym: Norta altissima
The photo above shows a close-up of the flowers and spreading,
linear fruit capsules of Jim Hill mustard as seen about one mile east of Celilo,
OR............mid March, 2005. Note how the narrow sepals are arched slightly
and how they have hooded tips. Note also the stout pedicels below each flower
or fruit in both the photo above and below, another characteristic of this species.
The
photo at right shows another image of the flowers of Jim Hill mustard as seen
about one mile east of Celilo, OR............mid March, 2005. Note the yellowish
veins in the petals.
Characteristics:
Jim Hill mustard is an annual or winter annual, which is found
as a weedy species over much of the United States. It is an erect, freely branched
plant with stiff hairiness near the base and smooth herbage above. Viewed from
a distance, it has a bushy appearance. The stems range from 30-150 cm tall.
The leaves are alternate, with the lower leaves coarsely divided into broad
lobes or leaflets. The upper leaves are reduced in size with finer or narrower
lobes or segments.
The inflorescence consists of numerous racemes at the ends of
branches, with each flower having 4 sepals (about 4 mm long) and 4 pale yellow
petals, 6-8 mm long. The seed capsules are long, linear siliques from 5-10 cm
long.
Plants often break off at soil level when mature, tumbling across
the landscape, scattering seeds with the wind.
Habitat:
Tumble mustard is common in small grain fields, rangeland, along
roadsides, and in open disturbed areas.
Range:
Although it is a native of Europe, Jim Hill mustard is found
over much of the United States.
It is found throughout the Columbia River Gorge between the
elevations of 100'-3000'.
- - -
Several photos of Jim Hill mustard observed along the old railroad bed in the Deschutes River State Recreation Area......April 7, 2024.
The photo above shows the pinnately compound
stem leaves of Jim Hill mustard as seen about one mile east of Celilo, OR........mid
March, 2005.
Paul Slichter